Blank entries should not be added

todo-example/spine/js/models/task.js

@@ -13,6 +13,10 @@
 
     Task.extend(Spine.Model.Local);
 
+    Task.prototype.validate = function() {
+      if (!$.trim(this.name)) return 'Task name is required';
+    };
+
     Task.active = function() {
       return this.select(function(task) {
         return !task.done;

todo-example/spine/src/models/task.coffee

@@ -2,6 +2,9 @@ class window.Task extends Spine.Model
   @configure 'Task', 'name', 'done'
   @extend Spine.Model.Local
 
+  validate: ->
+    'Task name is required' unless $.trim(@name)
+
   @active: ->
     @select (task) -> !task.done